nuvi2557LMT and Drive 50 LMT are off by miles

[flyboyy]

Both units were fine and then awhile ago (not sure exactly when, maybe a few months ago) one unit started showing off by miles, Then seemingly after the latest recent update they both are off by miles. I do not put in all time zone updates or things that do not apply to my area of Canada (West coast)

Any thoughts or suggests on the problem(s) ?
All the best,
Alan

[Garman_Nuvi]

Distance or Speed ?
Give an example so we can compare. Screenshots help

The Time Zone Map covers a lot more than a specific area.
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